Meanwhile, the authorities declared a nighttime curfew in the mainly Kurdish southeastern Turkish town of Sirnak and prepared army operations in the towns of Nusaybin and Yuksekova.

No group has claimed responsibility for Sunday's attack as yet but a car bombing near a military headquarters in Ankara in February that left 28 dead was later claimed by the Kurdistan Freedom Hawks (TAK), a splinter group of the PKK.

David Cameron has spoken to his Turkish counterpart Ahmet Davutoglu to express his "sincere condolences" and offer support.

The assistance includes "sharing information on the incident", the Prime Minister's spokeswoman said.